Solar cell technology: How it works and the future of sunshine

Why do we waste time drilling for oil and shoveling coal once there is a mammoth powerhouse within the sky up on top of us, causing out clean, non-stop energy for free? The Sun, an agitated ball of atomic energy, has enough fuel aboard to drive our scheme for an additional 5 billion years—and solar panels will flip this energy into an endless, convenient provider of electricity.

Image Source: Wikipedia

Solar power might sound strange or futurist, however, it’s already quite commonplace. You may have a solar-powered quartz watch on your wrist joint or a solar-powered calculating machine. Many folks have solar-powered lights in their garden. Spaceships and satellites typically have solar panels on them too. The yank house agency NASA has even developed a solar-powered plane! As warming continues to threaten our surroundings, there looks very little doubt that solar energy can become a fair additional vital style of renewable energy within the future. However specifically will it work?

How much energy are we talking about?

Solar power is wonderful. On average, each square measure of layer receives 164 watts of alternative energy (a figure we’ll make a case for in additional detail during a moment). In alternative words, you may stand a very powerful (150 watt) lamp on each square measure of layer and lightweight up the entire planet with the Sun’s energy! Or, to place it otherwise, if we have a tendency to line only one p.c of the Sahara with solar panels, we have a tendency to may generate enough electricity to power the entire world. That is the smart factor concerning solar power: there is associate degree awful ton of it—much quite we have a tendency to may ever use.

But there is a drawback too. The energy the Sun sends out arrives on Earth as a combination of sunshine and warmth. each of those area units implausibly important—the light-weight makes plants grow, providing us with food, whereas the {warmth} keeps us warm enough to survive—but we will not use either the Sun’s light-weight or heat on to run a TV or an automobile. We have to search out how of changing alternative energy into alternative styles of energy we will use a lot of simple, like electricity and that is specifically what solar cells do.

What are solar cells?

Solar power is rattling. On average, every area unit of layer receives 164 watts of other energy (a figure we’ll build a case for an extra detail throughout a moment). In different words, you will stand an awfully powerful (150 watt) lamp on every area unit of layer and light-weight up the complete planet with the Sun’s energy! Or, to put it otherwise, if we have an inclination to line only 1 p.c of the Sahara Desert with solar panels, we have an inclination to could generate enough electricity to power the complete world. That’s the good issue regarding solar power: there’s academic degree awful ton of it—much quite we have an inclination to could ever use.

Image Source : Wikipedia

But there’s a downside too. The energy the Sun sends out arrives on Earth as a mixture of sunshine and heat. every of these space units incredibly important—the light-weight makes plants grow, providing us with food, whereas the keeps us heat enough to survive—but we’ll not use either the Sun’s light-weight or heat on to run a TV or associate degree automobile. We’ve to look out however of fixing energy into different types of energy we’ll use a great deal of easy, like electricity. Which is specifically what solar cells do.

Just like the cells in a very battery, the cells in a very electrical device area unit designed to come up with electricity; however wherever a battery’s cells build electricity from chemicals, a solar panel’s cells generate power by capturing daylight instead. they’re generally known as electrical phenomenon (PV) cells as a result of they use daylight (“photo” comes from the Greek word for light) to form electricity (the word “voltaic” could be a relation to Italian electricity pioneer Alessandro Conte Alessandro Giuseppe Antonio Anastasio Volta, 1745–1827).

We can think about light-weight as being made from little particles known as photons, therefore a beam of daylight is sort of a bright yellow hose shooting trillions upon trillions of photons our means. Stick a photovoltaic cell in its path and it catches these energetic photons and converts them into a flow of electrons—a current. Every cell generates a number of volts of electricity, therefore a solar panel’s job is to mix the energy made by several cells to form a helpful quantity of electrical current and voltage. Nearly all of today’s solar cells area unit made up of slices of Si (one of the foremost common chemical parts on Earth, found in sand), though as we’ll see shortly, a range of different materials is often used similarly (or instead). Once daylight shines on a photovoltaic cell, the energy it carries blasts electrons out of the Si. These are often forced to flow around an electrical circuit and power something that runs on electricity.

How do solar cells work?

Solar cells convert the sun’s energy or solar energy into electricity. Whether or not they’re adorning your calculator or orbiting our planet on satellites, they admit the photoelectrical effect: the flexibility of concern emit electrons once a light-weight is shone thereon.

Silicon is what’s called a semiconductor, which means that it shares a number of the properties of metals and a few of these of an electrical non-conductor, creating it a key ingredient in solar cells. Let’s take a better inspect what happens once the sun shines onto a cell.

Sunlight consists of minuscule particles known as photons, which radiate from the sun. As these hit the element atoms of the cell, they transfer their energy to lose electrons, sound them clean off the atoms. The photons might be compared to the white ball in an exceedingly game of pool that passes on its energy to the colored balls it strikes.

Freeing up electrons is but solely the work of a star cell: it then has to herd these stray electrons into an electrical current. This involves making an electrical imbalance at intervals the cell, that acts a small amount sort of a slope down that the electrons can flow within the same direction.

Creating this imbalance is formed attainable by the interior organization of element. Element atoms area unit organized along in an exceedingly tightly certain structure. By compression little quantities of different parts into this structure, 2 differing kinds of element area unit created: n-type, that has spare electrons, and p-type, that is missing electrons, going away ‘holes’ in their place.

When these 2 materials area unit placed facet by facet within a cell, the n-type element’s spare electrons skip filling the gaps within the p-type silicon. This suggests that the n-type element becomes charged, and therefore the p-type element is charged, making an electrical field across the cell. As a result of the element may be a semiconductor, it will act as a non-conductor, maintaining this imbalance.

As the photons smash the electrons of the element atoms, this field drives them on in an orderly manner, providing the electrical current to power calculators, satellites and everything in between.

Are solar cells important for our future?

Solar energy has unbroken our species alive for thousands of years: heat, light, and crops. However, harnessing this energy to come up with electricity is, relatively, a really recent development. Because the Royal Society of London for Improving Natural Knowledge of Chemistry says, “The quantity of energy reaching the Earth’s surface each hour would meet the world’s current energy demands for a complete year… we have a tendency to not ought to gamble the lifestyles of future generations”. Additionally, technology is continually being improved and refined. But how, specifically, alternative energy be of profit in our lives and people of future generations worldwide?

The most obvious professionals of alternative energy, as we have a tendency to at solar Action Alliance indicate, a square measure that’s that it’s rife, property, free, secure, and reliable. Even in less sunny countries like the UK, there’s enough energy within the rays that reach the surface to come up with electricity. However, sunny locations like Calif., square measure ideal for a solar.

Just as individual households or businesses are able to do independence in reference to an influence provide, communities and cities will do a similar with whole communities living off-grid and being self-sustaining. In a world of restricted and strained resources, this can be a large advantage… and one that may be progressively necessary within the future.

Small, rural, and/or less affluent communities, regardless of however remote, won’t get to trust massive energy suppliers and their infrastructures or wait a protracted time for services to achieve them. Solar kits will reach any community and be fitted to homes, schools, clinics, and so on.

The fact that solar panels and systems square measure currently obtainable in varied sizes, shapes, and thicknesses conjointly make them much more versatile in terms of applications and wherever they will be used. New applications are perpetually being found and installations being created. There’s no reason to believe the longer term ones won’t be even a lot of exciting and liberating.